Welcome to "This week." Olympics on edge. New security fears with the games now underway. This morning, we're on the ground in sochi with all the breaking details. And our panel of experts on the unprecedented operation to keep our athletes safe. Plus, republican reversal. The president's going to have to demonstrate to the American people that he can be trusted. Speaker Boehner's sudden shift on immigration. And a stunning new report on obamacare. The powerhouse roundtable breaks it all down. And silent killer. We begin with the tragic death of actor Philip Seymour Hoffman. A Hollywood star's shocking death. Is heroin America's new hidden crisis? Hello, I'm Martha Raddatz. This morning, we're in New York City in the "Gma" studios. You see times square behind me because this city knows better than any in the world how to protect against the kinds of threats against sochi, hosting the olympic games. It's the first olympics in history that terrorists publicly vowed to attack. Former New York police commission ray Kelly and our panel of experts will be along in a moment. But we begin in sochi where the first weekend of competition is underway. There you see the medal cot. The U.S. Just behind Norway in the early going. Here's ABC's Matt Gutman. Reporter: A second gold minted for the U.S. Snowboarder Jaime Anderson spin, soaring in women's slopestyle final. Completing a U.S. Sweep of the daredevil event, with sage kotsenburg taking the game's first event Saturday. And hundreds cheering them on. And finding the Americans, not so easy. Tourists? No. Translator: No, hasn't seen them. Reporter: Swarming here, tens of thousands of security personnel. From the choppers in the sky over the opening ceremonies to the purple brigades of the plain clothes security in these ski getups. We left the venue, tried to bring American families out to talk to them, but they forbade us from doing so. They are extremely strict. The start of the games beset by controversy, with anti-gay protesters arrested in Moscow and St. Petersburg over the weekend. But perhaps the most glaring snafu came during the showcase moment in the opening ceremonies with president Putin presiding. The snowflakes were supposed to melt into olympic rings. But the fifth one malfunctioned. Hazardous hospitality, from faulty door handles to beer-colored water on the bee in my honey packet. And there's this. Johnny Quinn's solution to the bathroom door, bursting right through it. We watched because we do. And the picture and the sentiment so viral, we're getting more than the official view. For "This week," Matt Gutman, ABC news, sochi. Thanks to Matt. Let's bring in usa today's Christine Brennan, also an ABC news contributor who's covered 16 olympics. Joining us live from sochi this morning. Good morning, Christine. I want to start with the fabulous opening ceremonies. It looked fantastic. And just give us a sense of the mood. How the athletes are feeling, how it's going over there, how the crowds are. Reporter: You know, Martha, I'm an American, like so many of us, as we thought about this, family and friends, asking, should you go? The concerns, obviously, as a journalist, of course I was going. I'm here now. I have been here almost a week. And I have to tell you that security concerns are not front and center in my mind and have not been since I landed. That might sound surprising to people. But, for example, the opening ceremonies. That certainly was the three-hour time period where we were concerned and thought if there's something that could happen, it could happen here. To talk about a snowflake malfunction being the big glitch, the only thing, the only news that happened from the opening ceremonies, that would have been unthinkable a few months ago. That's the mood here. Things are going well. Let's talk about the handful of protesters that Matt mentioned. The gay rights demonstrators. Are larger protests expected? Can Putin just kind of forget about this at this point? Reporter: I don't think he can. This is one of the key storylines of the games. Even as sports started, the events have started, Martha, this story is pervasive. And I know it's front and center in my mind. We will continue to keep an eye on them. We don't see the protests. We're in the olympic ring, the secure area. But we know they're going on. And I'm guessing there will be more. Interestingly enough, keep an eye on the U.S. Athletes. Ashley Wagner, the American figure skater, she spoke out about equality and against the ant anti-gay law. And, of course, Brian boitano and other members of the U.S. Delegation. They talked about their concerns about the law. Just briefly back to security, you said you didn't feel much of a presence. They weren't checking your badges. Is it the same or do you feel a little more tension? Reporter: They are checking our badges. I want to make that clear. Our credentials are scanned. But in terms of what we are used to in the U.S. In big events, you know, with a show of force, guns, rifles, you see them everywhere at major sporting events. Nothing here. I have been here six days, I have not seen a gun. But I'm not saying that doesn't mean it's not secure, it's just a different kind of security. I found that surprising. But as I said, I feel very secure here.

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